In recent years, with the development of electronic technology, the touch display device such as smart phones, tablet PCs that is put into use in people's daily life more and more widely. Moreover, the touch display devices are more and more functional, which provides more convenience for users.
The touch display devices includes a touch panel. The touch panel includes a display unit and a touch unit on the display unit. For instance, the display unit is an OLED panel or a LCD panel. Wherein, the LCD panel includes a backlight, a thin film transistor array substrate, a liquid crystal layer and a color filter. The principle of the display unit is whether the white light from the backlight go through depends on the turning of the thin film transistor liquid crystal, and with the help of the color filter, the white light which across through the liquid crystal could display the corresponding RGB and other different colors. One of the OLED panel is a white-Light OLED panel. The white-Light OLED panel has only one kind of white light emitting material. The white-Light OLED panel uses white LEDs as the backlight. The white light passes through the color filter and generates color images. Whether the pixel unit emitting white light or no light is controlled by the thin film transistor. The pixel unit displaying the corresponding RGB and other different colors depends on the color filter. Compared with a self-luminous organic light-emitting display with RGB three color, the white light organic light-emitting display still retains the color filter. The touch unit includes a first touch electrode, a second touch electrode, and an insulating layer between the first touch electrode and the second touch electrode. As the touch unit is located on the display unit, the whole OLED could be overall thickness, and it is not good for lighting and thinning the touch display panel.